Isolation for power line conditioner?

I could be wrong, but I doubt adding isolation or coupling to your passive power line conditioner will have any effect on the sound of your system. I notice that of the above responses nobody has actually said it made a difference in their setups.

I have used Symposium Roller Blocks with Tungsten Balls under my Hydra and it does make an improvement. I have no idea why it does or why it should. I only know what I hear.

Jim Weil, the designer of Sound Application, has worked extensively over the years to try to limit the effects of mechanical resonances on his passive line conditioners and he is never fully satisfied with their immunity. This is a testimony to the fact that passive plc's sitting on the floor are subject to micro-shaking, resulting ultimately in some smearing of the audio signal. Whether isolation devices help more than they hurt is another question; I've never found external treatments to be overly helpful.
A related comment - I've often found the passive network boxes on networked cables to be quite vibration sensitive. Setting them directly on the shelf of a rack has resulted in very audible smearing, which is eliminated by hanging them or attaching them to the wall.
This is a subject I would really like to understand - and don't.

I continue to disagree with Stehno. Floorborne vibration is a far bigger problem, especially on raised hardwood floors, than airborne. The surface area of a network box for airborne interactions is small.

Onhwy61,
It does make a significant difference. Those airborne resonances have the same deleterious effect as those microphonous meanies in amplification and the like. go figure. 'tis why I go for coupling. Attainable. And all resonances go to mother earth. Even from ICs, power cords, and particularly, my Sonoran speaker cables. peace,warren

Not withstanding Jim Weil's efforts, the Line Stage in my system is improved substantially by being on a level 2 Mana stand.

I should also note that many of the better ac power cord efforts focus on resonances, the Harmonix comes to mind.